Lifting or screw jack.



No. 738,240. PATENTED JULY 7, 1903. J. M. MARZOLP.

LIFTING 0R SCREW JACK.

APPLICATION FILED MAY 8, 1903.

N0 MODEL.

13 7 14 1d 2 7.] x at W .josepiz/ Jfwv/er Jfzrzalf UNITED STATES Patented July 7, 1903,

PATENT OFFIC LIFTlNG OR SCREW JACK.

SPECIFICATION forming part of Letters Patent N 0. 733,240, dated July '7, 1903.

Application filed May 8, 1903. Serial No. 156,189. (No model.)

To all whom it may concern.-

Be it known that 1, J OSEPH MossLEE h/IAR- ZOLF, a citizen of the United States, and a resident of Homestead, in the county of Allegheny and State of Pennsylvania, have invented a new and Improved Lifting or Screw Jack, of which the following is a full, clear, and exact description.

This invention relates to screw-jacks; and it consists substantially in certain parts and details and combinations thereof, as hereinafter particularly described and claimed.

One of the principal objects of my invention is to provide a contrivance "or device of this kind which is simple in construction and organization, besides being effective and reliable in operation and comprising few elements, which are not easily broken and which may be readily taken apart for any purpose desired and again assembled for use.

A further object of the invention is to provide a contrivance or device of the character referred to which is capable of ready application to the lifting of weights or to other purposes for which the same may be employed, and one which is also strong and durable and not liable to get out of order.

The above and additional objects are attained by means substantially such as are illustrated in the accompanying drawings, in which similar characters of reference indicate corresponding parts in both views.

Figure 1 is a vertical sectional view of a screw-jack embodying my improvem ents,and Fig. 2 is a horizontal sectional view on the line 00 so in Fig. 1.

Before proceeding with a more detailed description it may be stated that in the form of my invention herein shown 1 preferably employ a body or stock of special construction in which is guided a vertically-movable screw, having the usual head for direct application beneath the structure or weight to be raised, and seated within said body or stock and cooperatively connected with the screw are the means by which the latter is operated, the entire organization being such as to yield exceedingly advantageous results in practice.

Specific reference beinghad to the accompanying drawings by the designating characters marked theron, 1 represents a body or stock of any desired height and other dimensions,

which is formed for a suitable distance from the base 2 thereof with an opening 3, the diametric distance between the sides or walls of which is practically the same throughout, said body or stock being formed around the upper edge of said opening 3 with a recess 4:, forming an annular ledge or shoulder 5, as shown, on which is preferably seated a wear plate or ring 6, upon which rests the lower end or surface of an operating-nut 7 for a screw 7 the latter to be presently described. At the part 8 thereof the said body or stock is cutout or slotted for practically its semidiameter and semicircumference to permit of the lateral insertion Within the body of a gear-wheel 9, having a worm-thread 10 on its circumference, said wheel having a central opening in which the nut fits, as shown, the sides or walls of said opening preferably being formed at diametrically opposite points thereof with vertical grooves or ways 11, in which corresponding keys 12 on the nut are received, it bein gin this or some equivalent manner that the cooperative relation between said nut and said gearwheel is effected. Formed in the upper end of the body or stock and leading to the said slot 8 therein is a central opening 13, the sides or walls of which are preferably slightly beyond the sides or walls of the recess-t and concentric therewith, it being noted that the upper part of the nut is somewhat enlarged,forming an annular shoulder 14 thereon, which prevents the nut slipping or working downwardly within the gear-wheel 9 during the operation of the device, as is apparent.

The upper part of the body or stock is formed with a slot or opening 15, substantially in line with the slot 8, and partially entering said slot or opening 15 is a worm thread or gear 16, the cylindrical body 17 of which is detachably fitted upon a shaft 18, having its hearings in brackets 19, located at the opposite ends of the slot or opening 15 and preferably integral with said body .or stock, said shaft being adapted to be rotated or turned in any preferred manner and from any desired source. Said worm thread or gear 16 engages with the corresponding thread on the gear wheel 9, and accordingly as the shaft 18 is turned in one direction or the other the said screw will be correspondingly raised or lowered, as is apparent. In fitting or as sembling the parts together the said gearwheel 9 may be slipped into place through the said slot 8 from without, after which the portion of the nut of least diameter may be placed within the central opening of the gearwheel, as already explained, and finally the screw may be inserted within the nut, and in the operation of the device it will be understood, of course, that while the gear-wheel and nut are rotated together the screw does not rotate, but moves vertically in one direction or the other, as mentioned, both the nut and gear-wheel being prevented from partaking of such vertical movement by reason of the confinement of the latter between the upper and lower sides of said slot or opening 8.

In virtue of the special construction and organization of elements shown and described it will be seen that the screw is guided in the opening 3 of the body or stock, while the sides of the operating-nut are supported or strengthened laterally all around by the sides or walls of both the recess 4 and the opening 13. The upper end of the screw is formed or provided with a head 20 of any preferred construction, the purpose of which is generally understood.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. A screw-jack comprising a stock having a vertical opening therein, and formed at one side with a slot leading to said opening, and extending substantially one-half of both the circumference and diameter of the stock, the latter also having another slot at the opposite side thereof, a screw working in said opening, and means partially located within said slots for operating the screw.

2. A screw-jack comprising a stock having an opening therein, extending upwardly from the base thereof, and terminating at its upper edge in an annular recess, forming a ledge or shoulder, said stock being formed at one side with a slot leading to said recess, and extending substantially one-half the circumference and diameter of the stock, the latter also having another slot at the opposite side thereof, and formed in its upper end with an opening cated in the said first-named slot, and having 7 a wormthread on its circumference, a nut fitting partiallyin said second-named opening, and partially in said recess, and adapted to turn with said wheel, said nut having threaded engagement with the screw, and a worm-gear engaging with the worm-thread of said wheel, substantially as shown and described.

3. A screw-jack comprising a stock having an opening therein, extending upwardly from the base thereof, and terminating at its upper edge in an annular recess, forming a ledge or shoulder, said stock being formed at one side with a slot leading to said recess, and extending substantially one-half the circumference and diameter of the stock, the latter also having another slot at the opposite side thereof, together with brackets at the ends of said second-named slot, a screw working in said opening, and said stock further having an opening in its upper end, leading to the slot first named, a wheel located in this slot having a worm-thread on its circumference, a nut fit ting partially in said second-named opening and partially in said recess, and adapted to turn with said wheel, said nut having threaded engagement with the screw, and'a worm-shaft having its hearings in said brackets and engaging with said worm-threads of the wheel.

4. A screw-jack comprising a stock having a vertical opening therein, and formed at one side with a slot leading to said opening,-and extending substantially one-half the circumference and diameter of the stock, the latter also having another slot at the opposite side thereof, together with integral brackets at the ends of this last-named slot, a screw working in said opening, and means for operating the screw, said means being partially supported by said brackets.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOSEPH MOSSLER MARZOLF. lVitnesses:

J. CLYDE MILLER, LAWRENCE L. CoTTER. 

